The present invention provides transgenic plants and plant cells thereof which have been transformed with the soybean calmodulin isoform (SCaM5) gene to exhibit greatly enhanced resistance to a wide spectrum of plant pathogens. The present invention also provides the expression vector containing SCaM5 gene and to host cells into which the gene in the expression vector has been introduced to plant pathogens-resistant plants. Transgenic plants expressing a heterologous SCaM5 gene show increased resistance to fungi, bacteria and viruses which normally infect the plants.